Aquatilis actually is a phase 2 unit, but due to overwhelming response during the launching day, Setia has put forward this phase 2 units to be sold in phase 1. Hence, the pricing for this aquatilis unit is a bit different compare to true phase 1 unit. Argentea unit for example, with buildup just slightly less 10 sqf, the starting price is RM 40k difference.
Although Cradleton units have larger buildup, but it contains a balcony and the yard area at the back is not fully covered with brick. So, I am not sure the if the usable buildup really significantly larger compare to SEH unit.
Don't forget SP Setia is very generous in the land pricing, as for the endlot unit, it cost additional RM 120k, but as return you can 15 feet extra land at the side for end lot unit if compare to the common 10 feet land. Therefore, from the point of investor, SEH unit seems like more valuable/worth in terms of capital cost.
Anyhow, from the point of own-stayer, Cradleton might be more worth value than SEH phase 1. As like you said, the materials specification for Cradleton is much better. Personally for me, Cradleton have two clear distinct advantages compare to DSL unit in SEH. First is like you said it is red clay brick vs sand brick, which is an absolute advantage. Second, Cradleton is a true GnG vs SEH FnG. This implies that the security features of Cradleton is way more advance than the SEH phase 1, although free alarm system is provided for SEH phase 1 unit, but not Cradleton unit (still need to install own alarm system).
Nonetheless, for own stay, personally still believe Precinct 3 Setia Ecohill still the most desirable/worth for value unit.

The cluster semiD unit is starting from RM 728k (36 x 78) with Agil PIDS perimeter fencing (used in Changi Airport), full red clay brick and two magnificent and exclusive Oriental Garden and Grassland Park within the housing area. Not sure if Stoneridge can match it in future, but so far still can't find any better units in Semenyih area with such pricing.
Yeah, cradleton is better for own stay, I pointed it out on materials just to tell ppl wondering why paying more on EM than SEH. Cradleton is only intercom, not alarm system? Ok my mistake. SEH cluster semi D just RM728k with high end security and red brick, really a good buy, as EM Merrydale 20x75 already cost around the same price. Stoneridge I asked, for lowest price cluster semi D around RM1.2mil, 32x75, if semi D 32x85 around RM1.4mil - RM1.5mil.