Does useing an SPL meter make a difference?

[Jase Fox]

Id just read on here the thread about SPL meters & although it was a very interesting & well put together explanation, do they really make a difference? For e.g. ive always trusted my ears were test tones are concerned & to me my test tone pattern all appear to sound the same from every speaker i have, now these meters are around £60 to by new & id hate to buy one & it not make much of a difference etc espec if my test tones were accurate in the first place, ok im trying to talk myself out of buying one just to use once but if i was sure it would make a difference in my sound & everything sounded much better or even then id go for it, so can anybody give me there experiences on using an SPL & IF SO ARE THEY WORTH IT? Was you sceptical at first like me? Id love your views? Thanks