An Avon Adventure 620 for extended cruising, probably not, but I'd have no issues with one for the Solent.
Definitely a love/hate boat on here... We had one from new for 4 years as our first larger RIB and absolutely loved it, used in all weather year round for trips from Poole towards the Solent and Weymouth. It's a much less serious hull than the other makes you list, a definite medium-vee, so will never be as good in more challenging conditions. Also typically comes with a fairly small fuel tank, and often more leisure oriented bench seating. Having said that, we found ours beautifully balanced with a Yam 115 4-stroke and never had any issues with it, and I used to take it out in a wide range of conditions.
We found after 3-4 years we had done everything we really could with it, and if we wanted to regularly go further needed a different boat for the range, storage, comfort, etc. As it happens for various reasons we then ended up with a much bigger and completely different blue water sailing yacht, but since then I've bought a big Ribtec as well for extended RIB cruising.
Personally I'd happily have an Avon Adventure 620 again for more local trips in e.g. Poole/Solent. Of course you can take it further given adequate planning, but if you really want something more capable of doing things like Scilly/Channel Islands, etc., I'd be going for something more like your list above to avoid swapping boats in a couple of years.
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