Don't worry, without risk using AP if you never have gap on your status,( Under the INA ,immigration officer in entry port may refuse the entry of a visa holder,even an AP holder,but he/she must give a reasonable excuse,if applicant think that it's necessary,an immigration judge will review the case) I think that using AP even more safer than using H1B,the officer may refuse your entry if he/she finds out that you no longer working for your H1B employor ,but he/she can't do it if you holding an AP,unless your I-485 had been denied.
By the way, if the immigration officer know that you have an AP,he/she may think it's unnecessary to give you a new H1B visa,so you don't need to show AP to him/her.
One of my co-worker had traveled to China with AP two years ago while his I-140/485 pending,go head.