Interesting thread this. Here's my two pence worth, for what it's worth 
I've owned both the HW40 & the Alecto & I've shot both in the comps.
Build quality is slightly better on the HW40, an example is the accuracy in location of the trigger adjustment screws of the Alecto. On mine I had to wiggle the key around to find the screw head. The mouldings are again slightly better on the HW40 although the Alecto does have the advantage of the textured grip and the palm shelf, however odd it appears to some people. The addition of chrome is a bonus as far as I'm concerned, especially on the trigger. An older HW40 has a dull finish on the trigger probably as a result of sweat. Makes absolutely no difference to performance it just looks a bit nicer IMO.
As for accuracy I personally found the the HW40 was more accurate for me. The grip on the Alecto was too small for me and I struggled to get a good hold. I can't make any comments over shot consistancy at different pump levels. I don't have a chrono and frankly as I only shoot at a maximum of 10mtrs in my back garden, I'm not bothered.
Who knows how reliable the Alecto will be over time. No one has that answer and comments negative or positive are pure conjecture. There is no proof either way at the moment IMO.
I sold both my HW40 & Alecto. The Alecto as previously mentioned because the grip was too small, the HW40 because I bought a Rohm Sport, a far more accurate pistol than either of the former two, again IMO.
Oh by the way shammo the HW40 is only available in .177 so there really was no point in stating that in your sig. If it was me I would change it to give yourself a little credibility, yet again IMO.
UBC Resident Cowboy
St Paul of 55
Been there, bought it, tried it, sold it