Benson said:
Armani and Paul Smith all the way...3 button single breasted.
Navy, Grey and maybe a city pinstripe for those lah-di-dah meetings/events!
Bespoke suits (especially Ozwald B and Richard James!) come in at about £1500. BBS what line of business are you in?
Off the shelf Armani/PS - £500-£700.
Ya just can't beat a good fitting suit....if you have to wear one that is!
Armanis are for people who don't wear suits to work.
I swear by Paul Smiths. I own 4 of them (oooh get me!) and they fit and wear superbly (although it cold be said I've put on a bit of weight since my last purchase!).
I have one Boss suit which I bought for a wedding, but the fit on most of those is very particular, but then it may suit you tho. Very good durability with thinner materials than normal.
Straight up Hackett for the over 40's. (age, not chest size). Will last a lifetime, but you will sweat like...*insert sweat analogy here*
Steer well clear of Ted Bakers. In the in-between sector (£300 ish) not really good (£400+ PS, Boss etc) but, aside form a (very

) fancy lining (which IS a consideration, it is about how you feel etc) they are not noticably better than a suit costing a couple of hundred less.
For VFM, I know people who swear by M&S, as the do a good range, and you can mix and match the trousers and suits, so you're not confined to, say, 34" waist with 40" jacket.
I doubt you;ll be able to justify to yourself getting a tailor made suits (which start at 7-800 for anything but bottom of the range) and there'll be a lead time of 6-8 weeks (or there was last time I checked).
I'd get a off the peg one first to find out what you want in a suit, and so you can compare bodyshapes etc.
Also, in general, if in between sizes, get the larger one. Then take it to a dry cleaners or preferably a specialist alterers. They can then taper the legs etc, basically do everything a tailor would do, although you'd be in the right ball park.
(One of the big 'cons' as such (although not really a con) is that most of the time when you see "personal tailoring", they dont have yards of fabric which they cut out your suit. They will have trousers and jacket which fit closest to your measurements, and then they will do as above, and taper legs, chest etc so it then fits you exactly)
Finally NEVER go shopping for one on a saturday, go wearing a good, double cuff shirt (wityh a good length sleeve), and look around and let yourself be pampered by old guys with tape measurers round their neck (i.e. a GOOD tailor, even if you have no desire whatsoever to buy one). They will be able to advise on what you can expect from a suit and the techiniques and fits which would flatter your shape. And they will give you the "been making suits 40 years man and boy... hardest game in the world..."