As someone who has rbed 4 pets on One character, I think I have the right to state what I believe without including the "I think".

I have an elin who has 2400 hp at lvl 73, she was my first rbed pet in wlo and like all noobs do, I scrolled her to con, so when she was lvl 100, she had over 1000 hp and 5 str. Now she has less than 40 str, so with brooch alone, she has about 700 atk. With AND Only with my eq, she can get 1500 atk, other than that, she has not been included in ANY fights since a year after I rbed her. Her hp sure does help her alot in fights, ds dragon only hits 1900 on her. So she estimatedly survives about 1.5 turns.

My Victoria is similar other than the fact that I fed her 10 foods some long time ago, same amount of con as elin but 11 lvls higher, with 90 more str than elin. She's able to get 2.2k atk with my eq, but as my eq is usually worn by Me, she only uses brooch and a sword.

I recently rbed my miss not too long ago, at lvl 64 rb, she has 2k hp. Her build is like victoria's except she has more potential. At the moment she can get 1500 mark and 700 spd.

Now here's my point.

My last pet is qlaya. Due to severe lack and scrolls and altogether lack of interest, she was barely scrolled at all. However, due to her rb stats, she received a moderately decent boost. She is lvl 85 atm, and has 1390 hp. HOWEVER, she can get 1700 mark with 900 spd. With ring she can get 1400 spd and can seal fed misses with ease.

The difference between these pets are:
1. Damage
2. Usefulness
3. Treatment
4. Level

700 hp more vs 60 less str and matk.
Brooch multiplies stats 2x, so 120 more atk and mark.

Now here's my final point.
The character of these pets is my main fire killer.
He has 3400 hp at level 136 rb. He can reach 2800 atk with that hp.
If I scrolled his con, I could max his str easily in a few levels and still have 2700 hp WITH some 100 more atk.

Why have a pet with high hp if it can't do anything?
Same for a char, why have a char with high hp if it can't do anything?
There's a great difference in stat arrangement, and for someone who not only has multiple pets on many chats, but also is a quester, for sure I can guarantee that extra hp is useless, you can easily get sealed by a 200 int noob who had 2000 hp, can easily get critted on by some noob with 1300 atk.
It is better to take advantage with what you have and utilize it to its fullest potential. And on that note, I've begun to scroll my chars' con and add accordingly.