some will tell you its the best diesel engine (well i will anyway!)
LMAO
the 130 gives you mix of added economy and performance over the 115
the 150 gives obviously gives you a faster car, and you get a few extras as standard however they cost more and the insurance is higher.
regarding economy i normally average 52-55 from a tank which lasts me ~ 550 miles
i personally thing the 150 bhp is still the best VAG diesel lump, esp when you look at the performance / economy against the MK5 TDI's
eg the MK5 GT TDI 170 has an extra 20 bhp & 30 Nm of torque but is only .4 sec quicker 0-60 and 2 mile quicker on the top end, and for these gains in performance you get 5 less miles to the gallon, which in my opinion is exactly progress.
what car have you got at the moment?
i expect you'd be happy with either the 130 or the 150