Beadlocks aren't too bad on more modern vehicles... such as the WK. On previous vehicles I've had, including the cragar wheels on the XJ, they tended to be really bouncey. I never had any issues with losing air pressure in them. The quality of them has improved since I bought my last set, So maybe they won't chip and peal like mine did. But I like'm.
With 6-8" of lift you WILL need more backspacing. The golden rule is you go up you must go out. For 6-8" You'd need about 4.00" of back spacing. If you still have both sets of your spidertrax you might be able to achieve that. Otherwise, look for something that will give you this.