Just my 2c.
For datalogging using a DMM, the 289 series is helpful if you truly need portability and a built in screen to see the waveforms and still be in the CAT III and IV protection level. But, the trade off is the DMM is fairly large and costs in the $500 range.
The new Agilent 1272A or other in the series, have specs to meet, or exceed that Fluke 87V, but it costs more than the 87V and less than the 289, ~ $340, $31 for the data cable, not sure if software is included and price ??. But many models at its level and more in the Agilent line have USB connections, and you can get the cable and use a laptop to interface and collect data, as needed, and still have the compact form of a standard DMM. There often are safety concerns bringing a laptop into a CAT III or IV work area, which you wouldn't need to bring if you used a standalone 289 as a datalogger. The 289 is ~ rated 2x more accurate than the Agilent, e.g. its basic DC is 0.05% vs 0.025%, but its a very subtle difference, and comparing the number of least significant random noise digit counts, they are about on-par.
For mics and amps, a scope is better, but they are typically not CAT III or IV rated for other work besides audio. Also, in the $500 range, there aren't many hand held scopes of good quality, one that is talked about often but few reviews in the Hantek DS1060; its not as good a scope as a dedicated desktop scope, and its not as robust as a handheld DMM, its reputation is not very established, its CAT III level safety is unknown, and that's the tradeoff.
In terms of quality to last you a 'lifetime', the better bet is Fluke and Agilent as a DMM and datalogger.
With an external i/o port, the onboard memory won't be an issue, as the external computer can store all the data you'd like to collect.