Casio MG 500. This is a quirky little guitar where the midi interface is built in. Its actually a nice guitar to play and has an onboard tuner, very handy. The midi tracking is slow but as it can be plugged into any synth via the midi out socket, its very versatile and very useful in the studio.
Casio MG 510. This is much the same as the MG500 but has a more traditional strat shape. A nice guitar to play with two single coil and one humbucker pickups. Even without the midi, its a desireable and versatile guitar.
Ibanez XING
Korg Z3. This synth was available at the same time as the Roland GR50 but it wasn't as good as the Roland machine. The sounds were all too artifical and it didn't inspire the guitar player the way the Roland did, It didn't last very long and Korg never bothered after this synth which is a pity as their keyboard sounds now are superb.
Roland GR50. This was the first guitar synth I bought and is still the one I use today for live performances. Later synths, although having better sounds, didn't have the editing capability of this machine so they weren't as versatile as this machine. If you are a live singer/guitarist, this is the synth I'd recommend
Roland GR1. This synth has all the features of the GR50 but as its a floor model, not the rack mounted like the GR50, it tends to get in the way. It will suit some players, especially in a band situation but for the solo performer who needs to operate drums and other aparatus, this synth is a little bulky
Roland GR09. A handy little synth, not as big as the GR1 and the sounds were definately an improvement on the earlier models but unfortunately the editing features were cut back so it wasn't nearly as useful as a live synth. It was excellent in the studio though and boasts some fantastic sounds and the tracking was quicker than earlier models.