I built an early tip up -6 when the slider was not yet available. I loved it and added the gas struts which greatly increased the rigidity. No doubt the visibility is superb. After I sold the -6, a good deal on a -7 QB kit became available, despite being a slider I couldn't pass it up.
Having built and flown both I will offer my 2 cents. Visibility: Hands down for the tip up. Ventilation: Slider clear winner. Construction difficulty: Probably a toss up, both have their challenges. Sealing water and air leaks: Tip up forward seal can be problematic, however rear skirt on slider is challenging. Tip up offers superior access to avionics, however increased chances of water damage. Entry/exit/baggage: Hard to beat the slider, especially if Supertracks installed (highly recommended). The glareshield brace makes a nice assist and can be a handy brace in turbulence. Watch the wind when opening the tip up. Rollover/Egress: Both offer limited options here, however forward roll bar on slider may offer additional frontal protection. Canopy breaker tool a must. Birdstrike Protection: I feel the slider would fare better in the event of a head on birdstrike by virtue of the more rigid separate windscreen and integral rollbar. Canopy Ejection/Removal: Provided the ejection mechanism is installed, pull the handle and the tip up is gone. Exiting the slider in-flight is a bit of an unknown, it would likely also be gone but not quite as graceful. Removing the slider canopy on the ground is a simple 1 man job, removing the tip up will require a helper.
If I had it to do over again, I would probably go with the slider, but I'm still jealous of you tip up guys.