Both printers include colour printing, USB connectivity, and borderless printing. Their most relevant distinctions are ISO black print speed and black copy speed.
DCP-T230 has ISO black print speed of 16 ipm, versus 11 ipm on L3350. DCP-T230 has black copy speed of 11 ipm, versus 8.7 ipm on L3350. L3350 supports Wi-Fi, whereas DCP-T230 does not. DCP-T230 has replacement black ink yield of 7500 pages, versus 4700 pages on L3350. L3350 has replacement colour ink yield of 7500 pages, versus 5000 pages on DCP-T230.
The paired specifications favour DCP-T230, particularly on ISO black print speed. The other model may fit better if its own strengths matter more to you. Consider the first model if Wi-Fi matters most; consider the second if ISO black print speed is the priority.