I ran a Polo 1.9Tdi the 105bhp PD engine for almost 10 years as the family car. For it's day it was a terrific engine; rattled like a taxi on the cold morning start-up but not so bad on the move. Great mid range pull without having to use the gearbox and an unrelenting 50mpg.
After 10 years it had served me well and I'd have happily bought another diesel. However I do hardly any miles at all now and fancied a change so swapped for a Polo 1.2 Tsi.
No I'll be honest and say the mid range in gear pull can't match the 1.9 oil burner. That said if you use the box the car goes very well, much better than you'd expect from a tiny 1.2. The astonishing thing is just how much pull is available from 1400rpm. At 70mph the little 1.2 pulls less revs than the diesel did which is just mad. It will happily tootle along and pull from under 30mph in 4th, something the diesel wouldn't. Small super efficient engines are the way technology is taking us. The little 1.2 vs 1.9tdi are pretty close on paper both generate about 100bhp so bare comparison as far as it goes.
I missed my diesel to begin with probably because I'd had it for 10years and become used to all the rattles and noises. But the little Tsi has won me over, it punches above it's weight, it's quiet and refined and does around 43-44mpg knocking around so it's not too far behind the diesel.
The which is better, diesel or petrol argument is just a waste of effort they are two different approaches. One isn't better than the other it's just different. Preferring one isn't a valid reason to shout down the other.
It's astonishing how much engine and vehicle development has moved on over the past 2-3 decades. I found a little comparison of the original MKI, Golf GTi pitted against a 1.2Tsi. The new car as quick, stops miles quicker, is more economical and doesn't bare comparison safety wise (i'll have a hunt to see if I can find it again)