I've owned this for about 7 or 8 years...basically from since it came out.

The best thing about it obviously that it enables you to add sounds to your guitar that simply couldn't not imagine before...and it can be damn handy.
The worst thing is that the tracking is slow and ghost notes can occur. This means that if you're not careful or you go too fast or strum too hard or not hard enough then you will get weird notes that were not quite desired. You can set the sensitivity of each string, though, to avoid this in most cases...takes some attention.

This was the first MIDI guitar system i tried and it's not surprising because before this there was virtually nothing. I think there was maybe the GR-50 and GR-1, and they were slower etc. This one could have benefitted from the expression pedal...you get with the GR-20 ! But you can always add your own i think.

Beware that the female output jacks are laid out & shaped in a way that will NOT let you use Neutrik jacks. You'll need something thinner!

The sounds in this are quite amazing, although i wouldn't use most of this for anything else than impressing the mates...
If you're careful, you can use the synth pads (which are VERY dynamic) to great effect, and if you put them through a good effects processor then you've got some fantastic sounds at your fingertips...
You can also use this as a regular MIDI expander for your existing keyboard! You can have 2 layers going at the same time, which is pretty cool. I used this with my shitty PSR-90 to make it into something acceptable.

If you have a Godin LGX (midi, electric and electro-acoustic separate outputs) you can have your regular electric mixed with the electro and then have a piano with strings via the GR-30. Now THAT makes a difference!
Also, you can do your solo through your electric amp and have it layered with 1 or 2 wild synth sounds.

Overall, i think it was a very expensive piece of equipment (i paid 4150 Francs, ie 625 €) but second hand it's probably quite a good deal now. If you use it. And put your mind to it, you really could!

The piano & organ sounds are quite good, the double bass sound is not bad either, and if you stick to the middle of the range you can use strings & trumpets and even trick people into making them think they're real.

- What connection types are there(analog, digital, MIDI)?
Inputs: 2 XLR, 6 TRS jacks (that's symetric...), digital SPDIF coax & optical (Toslink, not ADAT), RBUS (Roland proprietary interface that allows for the addition of various expensive boxes...such as extra analogue inputs or ADAT), MIDI in and out if i remember correctly.

- what is the sampling rate (bits/kHz)?
Good question. The machine is 24 bits, they say, but the converters are only 20. BUT this gives you extra headroom at mixdown, i think. No higher than 48 khz, but you can go down to about 32 khz, which can be useful to create different pitches without the use of a pitch-shifter: record at 32 and playback at the regular 44.1 or 48 and you get that funny high-pitched voice you used to get when playing an LP at 45 RPM.

- What storage format is used (ZIP, MiniDisc, hard disc...)?
2 GB internal IDE hard drive. Now you think that's small, it isn't. You can record a whole album with virtual tracks and still have space left. If you want, you can replace this drive with a 40 GB i believe.

- What types of synchronization are supported?
You cannot set the SPDIF to use external or internal clock: so if you can't set the device you're connecting to digitally you can end up having problems. For example, if you use a TC Electronic G-Force as an effects loop, you can't do that digitally unless you add a third device in the loop, or the VS will try to lock onto the G-Force while the G-Force is trying to lock on to the VS. I added in a Minidisc player with optical and coax inputs and it worked fine.
As far as pure synchro goes, you have MIDI and i think various modes exist in the menus but i never needed them so i can't remember.

- How many tracks can be recorded/read simulaneously?...
8 in compressed modes, 4 in linear mode. However, the Roland compression is a 3 to 1 lossless compression-decompression so i'm not sure there is much point in using the linear mode. Use 'MTP' mode.
You can playback 16 and 2 mastering tracks exist, so you can bounce these 16 to a virtual couple of extra tracks.
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You have 8 outputs on RCA connectors that can be used as direct outs. You can freely assign signals to these, and you can send what you want to pretty much any track or output too. Same for the monitor outs and headphones. It's a powerful mixer.
I put 8/10 cos the analogue outs are not symetric (which they are on the 2480), and that's a shame. Also, would have been good to have 2 digital ins that can be used at the same time, here you must choose between optical and digital.

- Is the general configuration/setup simple? - Is the manual clear and sufficient?...
Takes some getting used to, hardest thing to understand is the routing (as for the 2480...which works differently again, eeek!).
But the manual has a very clear, step by step approach, so you can't go wrong.
Overall, it's an easy machine to use, i find.

- Are the typical functions easily accessible?
Yup. One button gives you access to input or channel settings. Other features also have dedicated buttons.

- Are the A/D and D/A convertors transparent?
Sound ok to me! I usually bypassed the pres and A/D's though, and came in digital. That does definitely improve the sound if you're using some high-end piece of gear to do it with...
I'd recommend a high-end pre and compressor with a digital out.

- are the effects and filtres good?
The EQ is not so efficient or nice, but the onboard effects (optional with the VS8F-2 and VS8F-3 cards -- the latter takes third party VS plug-ins) are very useable.

- Are the dynamics respected?...
You've got to be careful not to reach that 0dB mark, of course, but if you avoid that then all is well, and you can make some very decent recordings indeed.