I think you should measure how much you want against how much you need it (or how strong he is), for example, if gameplay wise he was a 3, but in terms of much you like it he was 10, I would tell you to pull for him; compare with the servants you know that are coming (Like fairy lancelot, oberon, castoria etc...) Also take into account how many sq you have... (In my case, I need a strong archer, as I only have Artemis, and I really like him, so he is a necessary pull, I have 350sq, and I am planning to get castoria in Road to Lostbelt 7 - Avalon, so, as, a long as he comes home with no more than 150sq, I think he won't compromise Castoria). Or, switch to the dark side and whale it...xD