Hi, Tan. I'm going to go with the vague answer and say it all depends on what you want or can afford at the end of the day. If you're looking on buying a keeper that you don't want to spend too much money on in the early days of ownership with regard to tuning, then i'd go for the G60. Great engine, not too heavy, pretty good on juice, sings beautifully when it's kicked. Second best option (again, personally) is the 2.0, for the same reasons and the addition of 40+mpg with a not overly cautious right foot.
If you're looking at tuning then the VR is the most expensive option but still the best and most fun. I had a blower fitted, and 'savings' were a thing of folk lore. Even parts like exhaust downpipes took up the best part of a months wage. The VR felt a bit heavier on the front end than the others for obvious reasons, drank like a fish, servicing costs seemed quite steep at the time but i'm not sure if that's because I was living in Basingstoke at the time & paying southern prices. However, the sound it made under hard acceleration & the overtaking kudos was worth the money imo. Then there was the insurance... Ooch.
The 1.8 sounded good with an open pipe on it and went quite well considering it's an old small mill, but it was punished too much and a couple of valve stem seals went & eventually the head gasket and I didn't have the cash to mend her. It just never felt like it was going quite fast enough and fell foul to my lack of mechanical sympathy I think. I rarely saw more than 23 mpg from the valver, and I noticed a few guys on the web complaining about the same thing, although others had nothing but good things to say about their mpg!? Motorways weren't too bad in the valver, I thought it'd be quite revvy at high speeds but it was pretty good up to about 90 from what I remember. Insurance is higher on the 1.8 than the 2.0 for me now, could be different for you though.
All said and done you have to remember you're buying a 17+ year old car so go choose carefully whichever model you go for, read as much of this site as you can for tips on what to look out for when buying and don't be too hasty because there are a few about at the mo', and don't be shy about asking for a good test drive! Whichever one you buy you will have lotsa fun driving her.
What i'm doing now is going back to the drawing board, having the experience of a few different car models. I'm starting with the 2.0 which I think is the second best all round engine (I drive a lot of short, winding B roads in the lakes so second and third gear stomp & good handling is paramount, the good cruising mpg & speed is there for the motorway work for my days off. But, the G60 would be in my driveway if i'd had the money ;) ), I have a good set of coilovers on her already so all I have to do now is save money for the 1.8T conversion and sort the bodywork, wheels & paint out after winter when all the salt has buggered off. Simples!
That's about all I have dude. I hope some part of my ramblings may have triggered a spark of inspiration. They usually don't...