Actually, we've ended up buying 3 of them! One we've kept for us (and it's still in use several times daily, unlike most other kitchen gadgets that fall out of favour after a couple of months...), one went to the MiL and one is at my wife's Yoga studio. As I said above, our favourites are the Costa range for Americano and latte, although my wife also likes the Créma Intenso from one of the other ranges. As you say, some (latte, cappuccino and some others) come as 2 pods, I do the milk first in my lattes, followed by the espresso shot, ditto for the capp and the Cadbury hot chocolate (although we now use the Suchards HC - but at this time of year, the pods for that need warming otherwise they retain some of the syrup...) TBH, there's usually a £20 off your first order with the machines and to get free delivery you only need to spend £35 (IIRC) so for a tenner, you can try a few different varieties. We get the most used ones via Amazon, although I think they can sometimes be found cheaper if you shop around and look for special offers (and Makro stock some packs). I also like their Twining's Breakfast Tea, as does the MiL (a Yorksirewoman who likes her tea!).
We were also given a Senseo machine but only with the single cup bag holder. We've tried a couple of their offerings but much prefer the ease of use of the Tassimo as well as the coffe it makes! The only real gripe I have with the Tassimo is that the pods aren't recyclable.
Keep your eyes open for the machines on special offer - full price is a bit steep but we bought the first 2 at 1/2 price (in Sainsburys) and the 3rd came from a friend who got it through Costa shortly before having to cut drastically down on caffeine on doctor's orders. He never got to use it, although when he and his wife brought it up, we did give them both a cup of their choice!