I need some larger sails. Considering slalom/race sails with a freeride feel. I've been loyal to NP for years on my smaller sails but my local store keeps hyping up Severne.

I'm considering either buying one or two (6.5, 7.5m+ in size):
2023 Neil Pryde V8s
2023 Neil Pryde Speedsters
2023 Severne NCX
2024 Severne Moto

Thanks in advance, just looking for any informed POVs on rigging, handling, speed, wind-range.

I can't offer you a Severne v NP comparison, but love the Speedsters to bits. Light, super easy to rig, waterstart, stable, ridiculously comfortable and fast. Top end only 2 knots-ish different to my Evos. I only have bump and jump conditions locally and have to do big travel for any speed, so I love that they are just as happy on a slalom board, freerace or freestyle wave. I've even whacked one on my speedy . I have Evos in the smaller sizes and love them too so I'm guessing the V8s would be awesome as well. But it's camless comfort for me unless I'm somewhere with a chance of decent speed.

I ended up swapping from NP Race sails to Severne Overdrives because the NP race sails were very backhanded which kept pulling my front foot out of the strap at top speed. The OD's have the centre of effort more forward which works for me. I havent used the Speedsters or the Motos, but everyone i know who has used to Moto is a big fan of them.

I've gone from 2020 V8s, 5.2-7.7 to Patrik GT3 FRC 3 cams and love them. They are on RDM too 5.0-7.4. And awesome on foil. compared to V8 they are a solid build and super easy to rig & use. I expect to get more out of them than the V8 could offer. I ran RDM on the smaller NPs and SDM on 7.2&7.7. I've only used Severn's a few times and they weren't rigged to my liking but one local here has FoilGlides ODs & now the MOTO and he loves then and all on RDM. I think that build wise Patrik is better than NP. Severne will be the lightest&fradgile and more cams will be fastest and RDMs will produce best rotation & effortless handling.
Ive heard that the Speedster are best when fully powered. All of these sails will be awesome.

I've used NCX, OD, Mach2 and Moto. If it's freride you are after I would go with the Moto even though OD is my favourite. I just couldn't enjoy the NCX.

I use Severnes. At 67kgs ( probably 70 kitted up) I'm lighter weight. I think most of the 3 cam - 4 cam are designed for 80kg people powered up.
I love them but I'm often sailing them in patchy lighter conditions than they are designed for. Bottom end seems better with the twin cam Turbos than the Moto but I'm not great at rigging for power.
Moto is great powered up. Very balanced and easy to gybe. Rotation is effortless on rdm and nice and stable powered up. Easy to waterstart.
I have only used it well powered in the chop where it's great. I haven't had the conditions to check how stable it is speedsailing overpowered.
I have been using ODs for years speedsailing.
Turbos are good in chop but a bit unstable for overpowered speed sailing.