Sorry but I just had to join this forum as I was searching the web for information on Russian Vine x Knotweed hybrids and came across this post! There is some rubbish posted on here, so let's get a few things straight:
1) Russian Vine is a twiner not a clinger, and needs support. It will not attach itself to your walls!
2) Ivy clings to your walls, but it does not damage them in any way UNLESS they are already in a poor state. If your walls are sound, Ivy will simply cling to the surface and not 'penetrate' them in any way.
3) Russian Vine IS a problem - if you let it get out of control. It will happily grow anywhere, anytime, and at an astounding rate. It grows vigorously for much of the year and as a result other plants cannot compete.
4) If properly pruned in spring it will grow just where you want it and reward you with thick bunches of creamy white flowers late in the summer, going strong well into the latter part of the year.
5) Do not let the growing tips of Russian Vine come into contact with the ground unless you want it to smother your land - it quickly roots and is difficult to get rid off once an underground network is established.
I moved to a house where a vine had been allowed free reign for many years, and had almost completely covered a 20 foot cherry tree, as well as spreading across the ground. It took a lot of time to get it back to a manageable size but now it flowers much more freely and at the moment (mid October) provides the only colour in my garden. Treat it with a firm respect and it is a very useful plant