I have a V5 Performance. A V8, also Performance, was my first ski, after moving from over traditional sea kayaks. Had about 3 years or so before selling due to back issue. Great boat!I went kayakless for a few years then, when better and really missing being out on the water, found the V5. My last sea kayak was a Valley Nordkapp LV; beautiful boat! Before that, glass Tempest 165; before that Tempest 170 poly.
Before I say more, let me se if I might be coming from where you are. i.e unlike just about everyone here, and most on the sea kayak boards, I'm not a "professional", and paddling is not a "job". Let me explain that: I paddle because I love bobbing around in the waves, on the ocean (fresh water just doesn't smell right ya know?). For - gulp - fun.
Now, others might be saying "me too!" and "I'm not a pro, it's not my job". IMHO, if you have a GPS mounted to the deck, and tracking your speed to the second because it a BIG part of WHY you're out there, you're not having fun. Like those people on $4K bikes you almost hit with your car on windy country roads, who say the are ostensibly out for "fun". If you refer to what you wear while biking or kayaking as an "outfit", and your ensemble costs more than a decent 12 speed bike, you're not out there for fun. If it takes as much effort as a job, it's not for fun. Just me...
The V5 is a perfect kayak for fun. 1). the glass one I have is 35 pounds, and at 14 feet can be very easily carried around and put on/off a car. My V8, although about the same weight, when exposed to the wind - like carrying around ocean side parking areas - can be like a sail. At 5'9", keeping the bow or stern of the ground in wind can require care. 2). It can handle just about any conditions, certainly far more than I'll take it out in ... just look at the videos from that guy who helped Epic design if; HE'S a pro. 3). it can keep up with most sea kayakers - unless you run across some of the not-out-for-fun types, in their $4K composition boats and bike pants... 4). it does not require anymore "attention" than 21- 23" sea kayak to keep upright: you can sit back, take in the sights, ride the waves, dangle your feet over the side, take selfies ... all while taking a drink, eating a snack, 5). no tricks or certification needed to get back on it ... in almost any conditions. 6). it's got sa trunk too, so you can take things along.7) it's NOTHING like a plastic SOT: the V5 is a REAL, sea worthy, kayak.
I feel, like you seem to be looking firm, the V5 for me is not a linear proposition: this is THE boat for me, Not looking too "beat my time", race, etc, so no trade up.
Compared to my Nordkapp LV, usually considered an "on the faster side" sea kayak, I can get to the same places in about the same time. A little faster than my glass 165, faster than the plastic 170. The V8 was a little faster, and I'm sure any of the pro's here could have driven it much faster than I did, so if getting there fast is what you're looking for, get a V8. Excellent boat. I was just as "at home" sitting in the V8 as the V5. However, a big guy might have a different experience. If in the higher end of a boots weight design, a boat can feel less stable vs being on the other end of the scale.
i first rented a plastic V5 for a weekend. That is IMHO, and others have stated as well, not quite the same boat as the Performance. Tried a plastic V7, which I liked better than the plastic V5, but did not want that weight. From memory and limited time in the seat, I liked the V5 glass better then the plastic 7. I'd there was glass 7 at 35 pounds, maybe by losing the hatch, I might have gone there.
Hope that helps, and good luck. The V5 is not for everyone, but it is for me.