In reply to mountainbagger:
Yes, the resale value on them is incredible! These kids have only ever known Islabikes, but the oldest might be about to get a Hoy (if I win the eBay auction!).
When the kids were small, I agreed to be responsible for sourcing bikes. My friend has long-term health issues which means she can't drive. She can cycle so it was important the kids got bike confident early on so she could do nursery and school runs with them and she didn't know much about bikes! So I got them their first Islabikes very early on (and helped her to find a good bike for herself too). As they are close in ages, the first couple of bikes seemed like a lot of money to them, but now we sell the smallest bike and move the wee one up when the biggest needs a new one and doesn't seem to cost us anything now. Definitely worth the investment and the kids have been super confident on bikes from being tiny.