Wow! Being new to HF really makes some of these things confusing. I've used QRZ, eQSL and LoTW in my short few months in HF. I've asked around the club what everyone else thought and as with anything else got numerous answers. Really don't know whether to ask any more or not, so confusing.
I only submitted my contacts to eQSL to those who stated they respond to those, the same with the LoTW contacts. I was then informed "just upload all contacts to both. If someone decides to join either, your information will be there". Since I really would like the WAS from ARRL, I figured I needed to use LoTW for this. And now I use Ham Radio Deluxe (HRD) to upload all my contacts with a click of a button, which is a lot better. Again, being new to this, I haven't "downloaded" from either program back into HRD yet.
I started out with QRZ only, since i used it to check contacts and you could add them right in. Uploading and downloading ADIF files seems to get a little confusing, even with QRZ. So, I really don't know which, if any I like the best. I have received a couple "REAL" QSL cards and it was a great feeling. However, postage is getting ridiculous these days.
Well, no definitive answer to the original question, but at least I've been able to air out some of the frustration associated with all of it. 73's WJ4HCP (new vanity call).