Hi Darren,
I had a red GFI student which sounds similar to yours, 3 pedals and 2 knee levers, if I remember correctly it was LKR E - Eb and RKR E - F. I had it for a few years and got to the same stage as you are probably at now.
Whether to add new knee levers or upgrade to a better instrument. I looked into the options for adding knee levers which is expensive if you are adding genuine GFI parts. I considered getting someone to build them for me or having a go at making them myself. In the end I decided it was either too much money or time for the improvement in the functionality of the guitar.
I had been toying with the idea of a Universal for a while but was concerned that it may be too big a step up from the GFI, on the other hand it would give me years of learning, so I was unlikely to get to the same stage as I did with the GFI.
In the end I bought a Carter U12 from John Roche on this forum and I have not regretted it. Putting aside all the additional options of the Universal, the difference in quality and ease of playing was worth it in itself. The GFI student is a good starter guitar, I enjoyed playing mine and got a good sound from it, but once you have played a professional model you understand why the GFI student is classed as a student guitar.
If you think about it, the GFI is probably worth £500 - 600 resale value, 2 knee levers @ £300 + fitting if you are not confident in doing this yourself. That's getting on for £1k. I bought the Universal for around £1200 and I'm sure there are quite a few quality guitars out there that you could pickup for around the same.
The question for me was - Am I really serious about playing this instrument? The answer was YES, so I made the commitment, it took a while to get the permission slip from my wife

but I think I made the right decision.
Hope this helps
