Genghis,
Im not in total agreement regarding microlights and PFA group 'A' A/C being both equally cheap. The rapid grouth of microlighting over the last 10 years has attracted many newcomers into the sport and who all firmly believe that they have the cheapest flying. I don't think that's true.
Some types of proven homebuilt group 'A' designs are very, very cheap to purchase and are bargains in my opinion. Im a part owner in a FRED. It's a single seat open cockpit plane with a VW engine and it's worth a massive £2-3 grand. It uses 2.5 G/H mogas and cruises at 70mph. It was constructed over 20 years by hand to a very high standard from the plans.
What does your £2-3K get you in a microlight ... well not much!. Perhaps an old flexwing, or the most basic 3 axis machine of which both will have an unreliable early two stroke motor which will cost more to maintain and use more fuel than a VW (Rotax parts are very expensive).
Another factor is 'group 'A' is group 'A'' by which I mean hours logged in any group 'A' A/C whether that's a Club PA28 @ £100PH or your bargain PFA single seater still count for hour builders where as old group 'D' microlights do not.
With the new NPPL perhaps things will change - I hope so, as I could never understand the gulf between us grass roots sport PFA flyers and the Microlight brigade. Maybe with all these guys upgrading to group 'A' the ol' FRED may be worth somthing after all .... but I doubt it!
KNG