I have been having a play with my DCC gear again having received a number of chips from Bromsgrove Models and Hatton's. So far, I haven't seen much difference between the TCS 6 pin and the Bachmann 6 pin in the Class 24 I have been having a fiddle with. Now the general consensus from a number of points of advice all said the Bachmann chip was useful for putting in the trailing car of DMUs (which is partly why I got a few from Hatton's - I have two 108s and a 150/1 and 150/2 at present with 3 101s on order (including a 3 car set) along with the 411 EMU) but given that it is the Bachmann chip and the literature says it is tuned for the Graham Farish range I thought I would give it a go.
The only real difference I have been able to see is in the options for lighting - although I can't seem to get the random firebox flicker to work on the TCS chip to make it look like I have oil lights burning instead of the lights behind the discs. Maybe it is all too subtle. In any case, having put the conversion TCS drop in board into my Atlas GP-9, I am very pleased to be able to select a variety of lighting options so my cunning plan at present is to put Bachmann chips into Bachmann locos (and given the price is almost 2 to 1 against the TCS) where possible, and put TCS chips where it isn't (so I will be getting some Z2 chips in due course for my 04s and 08).
Now I don't have a big layout for fooling around with DCC - in fact it is merely a length of Kato Unitrack to test and program on - but it is nice to have all the locos sitting there with their lights on (assuming they have them - the Class 45 conversion doesn't) and being able to move the one in the middle without needing a lot of switches!