Hartke LH500 or LH1000 will give you a big clean sound, remember that 'flat' on the EQ is Bass and Treble on 3 and mids on 10.
Reliable and should not let you down. They are big-ish though.
The TX600 though lighter and smaller is not as goo or powerful IMO.
Hartke (the right one) are Probably one of the best bang for your buck around.
VT500 will be a fine amp with the sansamp circuit in it giving a great overdriven sound and second hand at around £300 is a good deal. It's cheaper compared to their other stuff as it is made in Korea instead of the states, but as far as I know no quality issues.
Question is where you put your money?
Slightly more refined head and less good speakers, or the other way round?!
The other thing of course is how quickly you need something, if it's now, choice is limited and jump on the Hartke, if it's not now, you may still jump in the Hartke but you have time to play a few.
My Hartke LH1000 served me well although ultimately I did change but for personal preference, not for lack of useability