I guess it depends on which Ian Weekley castle is being referred to. The ones I bought many years ago are now sold via Magister Militum. Hopefully this link works, I bought lots of the Italian style back in the early 90s
http://www.magistermilitum.com/manufacturer.html#order=name&limit=36&p=4&dir=ASC&cat[]=59633&cat[]=59613
As far as I am concerned the H&A castle is the premium kit on the market, and I backed that up many years ago by buying roughly 3 plus full castle kits plus the ruined walls. I have a similar amount of the Weekley castle parts.
I initially was taken aback by the comments that it doesn't suit modern 28s as I happily use Front Rank figs with it and they look wonderfully in scale. However on reflection it does depend on how many figures you want to jam in a tower and what base size you are using. The pics show a H&A section and a Weekley section with my scratchy Black Tree figs on them. The walls are just fine with an imposing height and the walkways easily fit one based figure. The H&A crenelations are 30mm spacing, Weekley at only 22mm, so H&A will take a fig per opening just fine.
Personally the walls stack up just fine unless you want to go city wall and have 2 figs fighting abreast along the catwalk like some mad Deeping Wall mass combat. I haven't walked many castle walls but the ones I did go on weren't wide enough for an Aragorn and Legless fighting side by side though for sure you might get 2 polearm guys trying to semi rank up. I guess it's up to your style of gaming what you are trying to represent on a catwalk and the base size you're using. If you're using unbased Perry plastics you could get 2 figs side by side ok.H&A catwalk is generally 38mm wide, almost enough for 2x 20mm based figs. Weekley is much thinner about 26mm.
Where the H&A castle falls down these days, and probably even historically with old Minifigs, is if you're trying for them to be something other than archer flanking towers. You'd be hard pressed to get 2 based figs sitting on each other in the tower facing in a similar direction. The internal diameter of 50mm is fairly restrictive if you're going the realistic figure pointing direction. Doesn't bother me but I know some people will fuss over it. The Weekley castle is a little better at 60mm square internally so you could sit 3 figs over each others bases.
The Weekley kit also has a glorious great tower - they call it a keep, but it doesn't feel very keepy to me, so I use 2 as the bastion towers at the entry to my castle setups inner bailey. They are more than enough to fit a trebuchet or two ala Minis Tirith. The H&A kits don't have anywhere to place small catapults on the walls except the gate piece and one other wall section with a chapel? Or something with crenelated roof over it. You could get small ballista on most wall section but not the towers unless you're using unbased crew.
Slightly off topic, but the info may be useful to someone. Baring in mind I bought Weekley 20 plus years ago some of the details in the mould was a bit muddy, could have been my batch too.
On topic, this doesn't grab me at all for this price. At half the price I might go yeah but I can't picture myself ever buying this especially the price it's going to be by the time it reaches Australia. The Renedra is far more interesting for me for a fantasy setting. The price still scares me, but I will be keeping my eye out for bargain sales so the pain is lessened as much as possible.