I flew the Bulldog (for more than a hundred happy, carefree hours) back in the 'pre avionics days' and I loved it. I was a spotty herbert fresh from school, however, and I'd have loved anything with a stick rather than a yoke, with a roundel on the wing, and a serial rather than a registration, mind you. Having to wear a bone-dome and flying suit just seemed to add to the 'military' experience - at least 'til the novelty wore off.
But it had its faults and it will probably never go down in history as a classic. It was as over-engineered as the Pup (which I still fly and love) and just as over-weight. The spin problems, the inadequate prop clearance for taxying on bumpy grass, were real enough, but the aircraft was difficult enough to fly an aerobatic sequence in to teach all of those useful lessons about energy management which others have outlined more effectively than I could (whereas the Chipmunk really was under-powered!). And in its 'yoof', when looked after by service engineers, and with adequate spares support, it seemed reliable enough for us always to have as many as we needed on the line - and enough for OUAS to be forever nicking one!
Max R8 summarised the beast very nicely, IMHO.
Someone asked us to "consider that the Bulldog's thirty years older than the 115 and that's why it was replaced" - my understanding is that the Bulldog could have gone on (with a 112FI(?) Spar mod which was designed, cleared and even fitted to one 'Dog - hope they're keeping that one for display use!) and that the reason it didn't was that they wanted a PFI solution, in which operating costs were the driving force, and where a modern gf llightplane was bound to be procured. Moreover, the costs of spares and support for the 'Dog had been escalated by the DA to a barely sustainable level (thanks BWoS), as anyone operating a civil one today will be finding.
Now who's going to take me up in a Grob and make me eat my words?
Dunno about EFTS, but anyone lucky enough to be on a UAS should be bloody grateful for whatever they're flying, although a bit of envy for what went before seems traditional. Some of us, I'm sure, wished we'd been able to experience the Chipmunk, and some of the Chipmunk studes could have looked back to the days when Harvard and Balliol 'advanced' flights were attached to UASs, or to the open cockpit magic of the Tiger and Hart! In 20 or 30 years, old farts like me will be getting all nostalgic about the Grob, too, I have no doubt.