Too good to be true? Yes, you'd have to snag a 110v transformer (second hand £35/40) and lug that heavy beast around, but hey. As mentioned though, do you need professional kit? Hitachi make some middle of the road stuff or you could go for a conventional hammer drill rather than an SDS - it'll be slower through the concrete, but still faster than a cordless, much more versatile in the long run and leaves you with a bit to spend on a cordless driver...
Really it comes down to what you are willing to spend. Firstly forget SDS unless you want expensive bits and plan on doing some intensive DIY. A good 18v hammer drill should be all you would need, if you needed an SDS drill you wouldn't be on here asking for advice. Secondly, by excluding NI-CD you can add up £100 to your bill, looked after NI-CD batteries work fine. Mine (dewalt 3ah) have lasted 3 years of moderate use and still hold a good charge. Definitely buy 2 unless you like stopping halfway through a job. While Li-ion batteries are better, ultimately its the current they supply that dictates power. Generic batteries seem to work ok although my generic one has aged noticeably more than the genuine ones. Makita, Dewalt, Bosch are all good names to start off with. If you want to drill concrete look for an 18v Hammer drill, preferably with 3ah + batteries. http://www.screwfix.com/p/dewalt-dcd785l1gp-gb-18v-3ah-li-ion-cordless-combi-drill-xr/86684 This is basically what you have specced up, I have the exact model with the NICD battery system and its yet to falter at anything I have thrown at it. For the money, you wont get a better spec, 66nm torque with 3ah LI-Ion batteries. As a reference point I also have one of these: http://www.screwfix.com/p/dewalt-dc100ka-gb-18v-1-3ah-ni-cd-cordless-combi-drill/73596 Seems to fit the bill but useless as anything other than a basic diy drill or driver. The torque is far less on this model and it lacks any real power. That said it leaves a Black & Decker (im aware they actually the owners of the dewalt brand) in the dust. Essentially higher torque and high AH batteries are the key things to look out for. Most drills have a clutch system as standard but really once you get above the £150 price point you have to ask yourself if you really need to pay £50 for an electronic clutch and an LED...
Update: First off I would like to thank every one for your help and advice. I though long and hard on which one to get and why and which eco system I would be more comfortable continuing in. I got some extra cash from presents and went for the: http://www.screwfix.com/p/bosch-gsb...n-cordless-combi-drill-coolpack-battery/69942 Comes with a 4 AH battery!! which alone costs close to the £ 150 I paid for the both on screwfix! So far I have used it just to hang a few pictures on the wall. It is the best drill I have used to date and eats through the walls like cutting a cake! Much quieter then a corded drill too in fact its so quite I can drill at night without bothering the neighbours. Naturally I went for Bosch top of the range drill bits as well and with a bit of forethought bought a pack of wood drill bits as well. (turned out to be a life saver because the misses decided to get a live tree last minute and we ended up with a stand that "screws" into the bottom of the tree) All in all very please and the guide light is a very welcome feature. Thanks again every one!!
I think you'll be very happy with that. I have a 5+ year old version of that and it's still serving me proud. The NiCad batteries still even get a serviceable life out of them. Happy drilling.