Hi Steve,
You can model, predict, plan or otherwise ask about antennas until you're blue in the face with multiple answers obtained and usually with negative connotations.
My best answer for you would be to sling it up and see how you get on.
Doesn't seem that "scientific" though does it?
If I'd listened to all the advice I was/have been given about antennas I don't think I'd have ever got an
antenna up! Yet with a tangle of lawn mower lead zig-zagging its way across my attic rafters and ladderline fed along with my homebrew ATU I'm working the world from 160m to 6m.
Admittedly that's mostly with FT4/8 but I've had as little as 5W QRP signals reach far afield as Chile, Japan and New Zeland never having so much fun or sense of achievement whilst doing it. Doesn't seem to do too bad with 10W SSB signals either having fun on many of the bands including CB frequencies.
Often others call these sort of things 'compromise' antennas with the belief that's it's not worth doing but any
antenna is definitely better than having no
antenna at all.
A horizontal V-dipole will 'model' as if having most of the signals being in the direction of the open end of the V but in the real world you will not notice such effects it definitely not being some sort of 'beam'. You'd be surprised that you'd be receiving signals from every direction and transmissions will have similar effect depending on the mercies of propagation. I used to think my East/West doublet would never bag me Africa and yet I've gained a few African countries for the log including South Africa.
When playing with any
antenna arrangement don't fall into the trap of having bad propagation conditions and then blaming the
antenna for it. You'll certainly be in it for the long haul to see how an
antenna behaves and I'd reckon at least a year of operation before you really know. The best
antenna won't pick up much when the prop is poor but the worst will pick up loads when propagation is good, so neither event gives you a good judgement.
Sorry for all the 'waffle' but as mentioned before (and I've just seen Alan suggest the same) it'd be best to give it a go and see how you fare. You may well be pleasantly surprised.
All the best,
Victor